All,
A few questions and comments on the Web Ontology Language (OWL) Guide
Version 1.0, http://www.w3.org/TR/2002/WD-owl-guide-20021104/, some of
which are just trivial typos.
1) The guide contains the definition of the WineYear class:
<owl:Class rdf:ID="WineYear" />
<owl:DataTypeProperty rdf:ID="yearValue">
<rdfs:domain rdf:resource="#WineYear" />
<rdfs:range rdf:resource="&dt;wineYear"/>
</owl:DataTypeProperty>
but this class does not appear to be present in the file wine.owl (or
food.owl) linked from the guide.
2) in this example OWL, the semicolon is missing from the first &owl;
entity:
<owl:ObjectProperty rdf:ID="locatedIn">
<rdf:type rdf:resource="&owlTransitiveProperty"
/>
<rdfs:domain rdf:resource="&owl;Thing" />
<rdfs:range rdf:resource="#Region" />
</owl:ObjectProperty>
3) Botany trivia - is Cabernet Sauvignon in fact a species as stated, or
just a variety? 8-)
4) Typo - change "Is" to "It" and add "of":
In our wine ontology, hasVintageYear is functional. A wine has a unique
vintage year.
That is, a given individual Vintage can only be associated with a single
year using the
hasVintageYear property. Is is not a requirement a FunctionalProperty
that all
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
elements of the domain have values. See the discussion of Vintage
cardinality.
5) Unique naming
The guide says:
> In the example above, we asserted identity between two distinct names. But it is just as possible for this sort of identity to be inferred. Remember the implications that can be derived from a functional property. Given that hasMaker is functional, the following is
> not necessarily a conflict.
>
> <owl:Thing rdf:about="#BancroftChardonnay">
> <hasMaker rdf:resource="#Bancroft" />
> <hasMaker rdf:resource="#Beringer" />
> </owl:Thing> Â¬
>
> It may simply mean that Bancroft = Beringer.
Well, does it? Either it is a conflict, or Bancroft = Beringer, but
which? If this is an application -dependent choice, are interoperability
problems likely if systems make different assumptions?
I think the point about explosion of properties has been made already -
with large numbers of distinct individuals, the number of
differentIndividualFrom properties required to express this becomes very
large. But presumably one could define a uniqueId property for each such
individual (inverseFunctionalProperty?) to achieve this?
6) typo -
differentIndividualFrom
This mechanism provides the opposite effect
from sameIndivdualAs.
^^^^^^^^^^^^^^^
7) typo - insert "of":
OWL provides the means to define a class via a direct enumeration its
members.
8) typo - remove apostrophe
One could distinguish four types of production
area's:
^
9) typo - Change "us" to "is"
vineyards are located in towns: Chateau Margaux us a vineyard in
Margaux, Avignonesi in Montepulciano
^^
Regards,
David.
--
/d{def}def/u{dup}d[0 -185 u 0 300 u]concat/q 5e-3 d/m{mul}d/z{A u m B u
m}d/r{rlineto}d/X -2 q 1{d/Y -2 q 2{d/A 0 d/B 0 d 64 -1 1{/f exch d/B
A/A z sub X add d B 2 m m Y add d z add 4 gt{exit}if/f 64 d}for f 64 div
setgray X Y moveto 0 q neg u 0 0 q u 0 r r r r fill/Y}for/X}for showpage